The present invention relates generally to machines for automatically producing armed surgical needles, i.e., surgical needles having sutures attached thereto, and more specifically, to an infeed apparatus that automatically sorts needles and feeds them for further processing, for e.g., to an automatic swaging device.
Most armed surgical needles, i.e., needles having sutures attached to one end thereof, that are in present use by surgeons and medical personnel, are manufactured utilizing manual and semi-automated procedures such as those described in U.S. Pat. Nos. 3,611,551, 3,980,177, and 4,922,904. For instance, as described in U.S. Pat. No. 3,611,551, manual intervention is required by an operator to accurately position a suture within the needle for swaging and to adjust swaging dies to increase or decrease swage pressure when suture strands of different gauges are to be swaged. This process is costly in terms of man-hour labor and efficiency because manual positioning is required for swaging to take place.
Presently, suture material may be supplied wound on a bobbin, or, a king or driven spool before being cut and positioned within the swaging end of a surgical needle. In U.S. Pat. No. 3,980,177 the suture material is fed from a spool and taken up on a rotating tension rack where uniform length strands are subsequently cut. Thus, the length of the suture is determined by the size of the rack and manual intervention is required to prepare the rack for the cutting of the suture material wound thereabout. Moreover, manual intervention is required to change the rack each time a suture strand of different length is desired.
In U.S. Pat. No. 4,922,904, the suture material is supplied wound on a bobbin and is fed through various guide means and a heater for straightening the material, prior to insertion within the crimping cavity of the surgical needle. In one embodiment shown therein, an elaborate television monitoring means is required for aligning the drawn suture within the crimping cavity of the surgical needle prior to swaging thereof. In the. same embodiment, a rotary encoder device is used to determine the length of suture material unwound from the bobbin prior to cutting. In an alternative embodiment, after swaging of the indefinite length of suture material to the needle, the needle-suture assembly is fed a predetermined distance prior to cutting to obtain a suture strand of predetermined length. Thus, to obtain uniform lengths of suture material every time requires careful manipulations and precise controls, and the processes used to accomplish these tasks are also costly in terms of man-hour labor and efficiency.
U.S. Pat. No. 5,065,237 describes the automatic sorting of mail such as envelopes using conveyors with black and white stripes, a video camera for detecting the edge of a mail piece, and a limited function robotic device for picking up a mail piece based on the leading edge of the mail, but it is not capable of singulating, imaging or sorting surgical needles.
U.S. Pat. No. 5,150,307 discloses a computer controlled sorting apparatus for separating and sorting plastic items having a means for converting an image into digital signals for singulation, but is not capable of determining orientation of needles, the precise placement thereof, or of picking a needle up for placement in a precision conveyor.
U.S. Pat. No. 4,651,879 discloses a bottle sorting station having a conveyor, a transfer device and an engagement device for sorting bottles, but does not singulate from bulk, nor is it able to determine orientation of a surgical needle or provide precise placement of the needle after sorting.
It would be highly desirable to provide an armed needle production and packaging system that is fully automated and that includes means for automatically feeding surgical needles to an automatic swaging machine for the swaging of sutures thereto.
It would also be highly desirable to provide in an armed needle production apparatus, a needle sorting device that can efficiently and accurately orient a needle for subsequent transference to an automatic swaging station.
Even more desirable would be the provision of a control system to maintain the efficiency and integrity of the needle sorting and transferring function.
It would be desirable to provide a needle sorting and singulating apparatus which provides precise pre-positioning of individual needles before imaging to minimize the rejection and recycling of overlapping and nested needles.
It is a further object of the present invention to provide an improved and moveable precise positioning hard stop which will accurately locate the butt end of a curved needle within 0.001 of an inch for hand off to an automatic swaging apparatus.
Accordingly, it is an object of the instant invention to provide an automatic needle sorting device for singulating and conveying individual needles to a needle processing location.
It is another object of the instant invention to provide a cost effective needle sorting device that virtually eliminates operator exposure to repetitive manual operations.
It is another object of the instant invention to provide an automatic needle sorting device that singulates and positions individual needles in a precise and predetermined orientation for transfer to an automatic swaging station for attaching armed surgical needles thereto.
These and other objects of the present invention are attained with an apparatus for automatically sorting needles and preparing them for automatic swaging and packaging in a reduced size organizer. The needle sorting device comprises at least one receptacle means for holding a plurality of needles, the receptacle means being provided with a means for singulating the needles into a single file of individual needles, and then depositing individual needles on a first translucent indexing conveyor means to provide a moving line of singulated needles for further imaging, manipulation and handling. A first set of remotely located video camera means obtains images of the individual needles upon the first conveyor means and the images are subsequently digitized to enable processing by a control system computer. The digitized signals are processed to obtain both positional and orientation data for individual selected needles on the conveyor. Inasmuch as a curved needle has a sharp point on one end thereof and a butt end on the other end thereof for receiving a suture, it is necessary to determine not only the needles position, but also its orientation.
A robot assembly is provided for transferring individual selected and imaged needles from the first conveyor means to a second precision conveyance means for conveying the needles to an automatic swaging machine.
The control system computer additionally generates instructions for use by the robot assembly based upon the positional and orientation data of the selected unoriented needle. The robot assembly receives the instructions from the control system so that a robot arm may grasp each selected needle and position it in an engagement device located upon the second conveyance means.
One or more orientation devices are provided to ensure that the needles are all uniformly oriented up to within 0.001 of its specified position upon the second conveyor means, so that a transfer for subsequent swaging can effectively take place.
The needle sorting system may also be provided with a second video camera means and a second robot assembly means that operate in the manner as described above on a second conveyor. The redundancy is designed in the system to ensure that a continuous and uninterrupted flow of about 60 needles/minute is supplied to the automatic swaging station.